Clinical Trial for Immunostimulating effect of Physta(R)/Eurycoma Longifolia Extract - A Randomized Controlled Trial

INTERVENTION: Duration: 4 weeks Test material: Eurycoma Longifolia root extract.......200 mg/day Once/day Duration: 4 weeks Test material: Rice powder.......200mg Once/day CONDITION: Healthy adults PRIMARY OUTCOME: Scoring of Immunological Vigor; Immunological Parameters SECONDARY OUTCOME: Total testosterone, Free testosterone; Questionnaires (POMS, Likert); Blood test; Urinary test; Physical examinations; Marketing questionnaire INCLUSION CRITERIA: a) Healthy adults, who feel fatigue daily b) Persons whose ages are between 40 and 59 years old c) Low immunity score (SIV less than 23) on visit 1's examination